Sen. Bob Corker, R-Tenn., is "contemplating" whether he will seek a third term in 2018, Politico reports.

Corker, who chairs the Senate Foreign Relations Committee, said Monday, "I think everyone in the Volunteer State knows, as they did in 2012, that running for re-election has never been an automatic for me. While we are in a strong position, I am still contemplating the future and will make a decision at the appropriate time."

He added that his record of making deals in the Senate, such as introducing a bill allowing a vote on the Iran nuclear deal and his work on the 2013 immigration reform bill, could result in a primary challenge.

"After spending a lifetime in business, I ran for mayor of Chattanooga as a civic endeavor, and I continue to do what I do because I wholeheartedly believe in public service," he said. "That approach allows me to truly throw myself into the job and make decisions based on what I believe is best for Tennessee and our country without thinking about the next election or the next potential opportunity."

"As far as what am I going to do in the future, I'm still contemplating the future," Corker said. "It's a tremendous privilege to do what I do, and to weigh in on the big issues . . . But I have not decided what I'm going to do in the future."

Despite his misgivings, many Republicans think Corker will run again. He raised $6.5 million by the end of June, and retains Ward Baker, who ran the GOP’s Senate campaign arm last year, as a consultant.